Office



Patented Mar.. 1o, 1891.

' (No Model.)

W. MGSHANR SAFETY VALVE. No. 448,065,

' JZZowzey UNITED STATES PnTnNtr- OFFICE.

\VILLIAM MCSHANE, OF ST. JOHN, NEW BRUNSXVIOK, OANADA, ASSIGNOR TO THOMAS MCAVITY, JOI-IN A. MOAVITY, AND GEORGEMCAVITY, ALL OF SAME PLACE.

SAFETY-VALVE.

SPECIFICATION forming part or Letters Patent No. 448,065, dated March 1o, 1891. Application filed July 26, 1890. Serial No. 360,069. (No model.)

seeking to provide a simple "construction ofvalve which will be certain in its operation and which can be conveniently adjusted to blow off at any desired pressure; and the invention consist-s incertain novel constructions and combinationsv of parts, as will be hereinafter described, and pointed out in the claims.

In the drawings, Figure 1 is a longitudinal section of my improved valve. Fig. 2 is an end View of the bottom piece or base. Fig. 3 is a view of the top of the case. Fig. 4 is a bottom view, part in section, of the valve proper; and Fig. 5 is a detail view of the regulating-disk. Figs. 6 and 7 show somewhat different constructions, all of which will be described; and Fig. 8 is a detail view of bottom of case and valve arranged therein.

The bottom piece or base part. A is adapted at its lower end, at a., for connection with the boiler and is provided at its upper end with the valve-seat, formed with outer and inner rings B h, connected by spider O, up through which spider the steam escapes when the valve, presently described, is opened. Within the inner ring b and extended down therefrom I form the socketD for the lower extension of the valve-stem, as will be hereinafter described.

The casing E is threaded at its lower end on the base A, and is provided at its opposite end with the top piece e, having the spider F, supporting the central internally-threaded ring or collar f, in which is threaded the bearing tube or bolt G, which serves to adjust the tension of the valve-spring.

The valve proper II is provided with portions I t to bear upon the outer and inner rings B b of the seat, and is formed on its under side with the depending stem or extension which tits and moves longitudinally in the socket D. This extension J is tubular,

has its lower end open, and its base communicating at its upper end with the central opening h in the valve. I form this `eXtension .I with side grooves j, down which the steam may pass to the lower end of said stem when the valve is opened, and also with lateral openings or ports K for the passage of the steam into the said stem. its upper side the valve proper H has a 'socket or concavity L, in which fits the lower end of the tubular stem M. This stem M is preferably formed in two sections N O, the upper section N being threaded into the upper side of the lower section O and having its upper end extended through the bolt G. The lower section O is formed at its lower end to tit in the socket h in the` upper side of the valve II, and is .provided at its upper side with a tubular nipple o threaded internally to receive the section N and formed externally to tit in the lower end of the valve-spring P. The section O also has a iange p, which serves as a bearing for the lower end of the spring I). This spring encircles the stem M and bears at its upper end against a bearing-ring Q, which is pressed upon by thelower end of the adjusting-bolt G, which obviously may be set to give the spring Pany desired tension on the valve. The jam-nut g on the bolt G serves to lock it in any desired adjustment. By the described construction it will be seen that the spring serves to hold the valve seated under ordinary pressure; but under any unusual pressure the valve will be lifted, compressing the spring, and the steam will escape up the hollow stem. On the case E, over the upper end of the bolt G and valve-stern M, is placed the hood or cap R, which is perforated, as shown, and is threaded on the top part e, and may have its base-flange perforated to receive the shackle of a padlock S when a lock-up valve is desired.

The perforated disk or cap T has a central holeU smaller than the mouth of stem M and outer holes d, and is supported above and I concentric with the stem M. This disk serves to regulate the escape of steam from stern IWI, and is supported so it may be set up or downup to expose the full area ot the outlet of the Centrally in IOO stem or down to contract such opening. It will be'understood that in its lowest position the disk Will be abutted by the upper end of the stem M when the valve is opened, but that When raised the regulatingdisk will be above the end of the valve-stein, even when the latter is in its uppermost position.

In the construction shown in Fig. l the disk T is supported on a nut t, screwed on the top of the cap-piece R.

In Fig. 6 the Valve-stem is shown extended above the'cap-piece, and is threaded to receive the nut t, a jam-nut V being provided to secure the nut t in its-desired positions.

In Fig. 7 is shown a construction similar to that shown in Fig. 6, except that in such Fig. 7 the cap is omitted.

In operation it Will be understood that when the valve-stem abuts 4the regulating-plate it closes the openings u, leaving only the opening U for the exit of steam, and as such opening is smaller than the Imouth of the val-vestem the discharge of the steam is consequently retarded.

By means of the lever W the valve vcan be opened at will when so desired.

Having thus described my invention, whatI claim, and desire to secure by Letters Pat ent, is

1. A safety-valve, substantially as described, having its valve proper provided with a tubular stem hollow from end to end for the passage ot the steam into the atmosphere, substantially as set forth.

2. In a safety-valve, the combination, with the valve having a hollow tubular stem open at its end, of a regulating-disk supported and adjustable toward and from the open end of said stem, substantially as set forth.

3. The combination of the valve having the tubular stem open at its end, the disk supported concentrically above said open end of the valve, the nut supporting said disk, and a support to which said nut is screwed, whereby the disk may be adjusted up or down, substantially as and for the purposes set forth.

4:. The combination of the base A, having the valve-seat and provided with the central socket D, and the valve proper fitted to said yseat and having a hollow tubular stem and a lower extension, the latter being arranged to operate in the socket D, all substantially as and for the purposes set forth.

5. The combination, With the base having the valve-seat, of the valve having a lower extension and provided with a tubular stem formed in sections N and O united, substantially as set forth.

G. The combination of the base having the valve-seat and provided with the socket D, the valve proper provided with a depending extension J, Iitting in the said socket and having in its upper side a socket or concavity 7L, and the tubular valve-stem formed at its loWer end to fit in said socket 7L, substantially as set forth.

7. The combinationof the casing, the cap thereon, the valve having its tubular stem eX- tended into said cap, the regulating-disk, and the nut supporting said disk and threaded on the cap, all substantially as set forth.

8. The combination of the valve having the tubular stem, the regulating-disk vhaving an opening U in alignment with said stem and opening u, and adjustable supports for the said regulating-disk, all substantially as set forth.

9. The improvement in safety-valves, substantially as herein described and shown, consisting of the base A, having vthe valve-seat and the central socket D, the valve proper fitting the valve-seat and having a socket h, and a lower tubular extension J, fitting in the socket D and provided with external grooves and lateral ports K, the tubular stem M, having sections N, and a section O, formed atits lower end to fit in the socket 7z,and provided with a flange p, the bearing-ring Q, and adjusting-bolt G, and the spring on the stem M, arranged to bear between the flange p and the ring Q, all substantially as and for the purposes set forth.

IVILLIAM MCSHANE. lVitnesses:

DONALDSON HUNT, AMoN A. WILSON. 

